Oxygenated Biofuels from Butanol for Diesel Blends: Synthesis of the Acetal 1,1-Dibutoxyethane Catalyzed by Amberlyst-15 Ion-Exchange Resin

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• 作者：Nuno S. Graa ; Lus S. Pais ; Viviana M. T. M. Silva ; Alrio E. Rodrigues
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2010
• 出版时间：August 4, 2010
• 年：2010
• 卷：49
• 期：15
• 页码：6763-6771
• 全文大小：305K
• 年卷期：v.49,no.15(August 4, 2010)
• ISSN：1520-5045

文摘

The synthesis of 1,1-dibutoxyethane or acetaldehyde dibutylacetal was studied in a batch reactor by reacting butanol and acetaldehyde in a liquid phase, using Amberlyst-15 as the catalyst. The reaction equilibrium constant was experimentally determined in the temperature range 20−40 °C at 6 atm, where K_a = 0.00959 exp[1755.3/T (K)]. The standard properties of the reaction at 298.15 K were estimated: ΔH° = −14.59 kJ mol⁻¹, ΔG° = −3.07 kJ mol⁻¹, and ΔS° = −38.64 J mol⁻¹ K⁻¹. Kinetic experiments were performed in the temperature range 10−50 °C at 6 atm. A two-parameter kinetic law based on a Langmuir−Hinshelwood rate expression, using activity coefficients from the UNIFAC method, was used. The kinetic parameters are k_c = 2.39 × 10⁹ exp[−6200.9/T (K)] (mol g_cat⁻¹ min⁻¹) and k_s,D = 2.25 × 10⁻⁴ exp[3303.1/T (K)]. The activation energy of the reaction is 51.55 kJ mol⁻¹. This work is an important step for further implementation of an integrated reaction−separation process, such as a simulated moving-bed reactor.